1. Field of the Invention
The present invention relates to a laser imager used in network-connection with a medical modality or with a workstation.
2. Related Background Art
A laser imager for medical use is defined as an apparatus for writing an image transferred from a medical modality such as computer tomography (CT), magnetic resonance imaging (MRI) or digital subtraction angiography (DSA) onto a film by using a laser. Concerning the connection between the medical laser imager and the medical modality, a conventional video interface is being replaced with a digital interface using RS422 or with a digital interface in the broad sense such as a network interface, for example, Ethernet.
Normally, information concerning an image is managed by separating image information from header information within the medical modality. The image information means a gray-scale image itself taken by the medical CT, MRI, DSA, or the like. The header information is overlay information, for example including a patient name, a patient ID, a modality name, acquired (photographed) date and time, acquiring conditions and the gray scale and the like. With respect to the video interface being used for connection, an image indicated on a CRT monitor in the medical CT, MRI, DSA or the like is transferred to the laser imager by scanning data in a frame memory including the header information overlaid on the gray-scale image and then converting it into a video signal. Here, character information in the header information is overlaid after it is converted into fonts. If digital interface such as RS422 is being used for connection, the data in the frame memory including the header information overlaid on the gray-scale image indicated on the CRT monitor in the medical modality is transferred to the laser imager as it stands.
An operator determines the setting of window information for transferring the image to the laser imager while observing the CRT monitor as to the medical modality. Further, for image output by the laser imager, the operator sets through a keypad connected to the laser imager, format information for determining a layout for printing a plurality of images on a single film, shape for nonlinearly converting shades of gray in the image, starting to store images, starting of print, etc.
Recently, the network interface such as Ethernet tends to be used in accordance with the increasing popularity of a workstation of the medical modality. In case of the network interface being used, the American College of Radiology (ACR)/National Electrical Manufactures Association (NEMA) format standardized in the U.S.A. is often used for data format between the medical modality and the laser imager. With the ACR/NEMA format, the image information and the header information are transferred as a single file to the laser imager and in the laser imager, management by separating the image information from the header information can be employed.
Further, the X Window is standardly used as protocol for interactive indication of a workstation. An operator can operate each workstation in network-connection to execute application software on the other workstation and then to indicate an interactive indication on the workstation at an operating end.
Incidentally, a single ordinary medical image substantially has pixels of, for example, 512xc3x97512 to 1024xc3x971024. On the other hand, a print image of the laser imager for medical use is normally a 14xc3x9717-inch film with pixels of 4096xc3x975120 matrix. Therefore, it is usual that there are a plurality of images arranged such as three rows and three columns in a single film. A scaling (i.e., magnification change) process is normally effected for the image information and the overlay information in the laser imager in order to print a plurality of images as large as possible on the film.
There are roughly three methods used for the scaling process. The first method is the Pixel Replication method, in which original data closest to a position of an interpolated pixel is used as interpolation data as it stands. The second method is the Bilinear method, in which four original data closest to a position of an interpolating pixel are selected from a two-dimensional space and those are used for linear interpolation. The third method is the Cubic Spline method, in which sixteen original data closest to a position of an interpolated pixel are selected from a two-dimensional space and those are used for Cubic Spline interpolation.
The Pixel Replication method preserves the edge of an image, while the Cubic Spline method can blur or smooth the edge, depending upon employed coefficients. Since it is desirable to preserve the edge for the font information as character information, the Pixel Replication method is suitable for the scaling process of the font information. Further, the Cubic Spline method is suitable for an image of a medical CT or MRI, while the scaling by the Pixel Replication method is suitable for an image of DSA.
(1) Since in the above-described conventional examples the header information and the image information is respectively managed in separate files, the overlay information including the window information, the format information, the gray scale, etc. must be first converted into a single ACR/NEMA format file in order to transfer the files from the medical modality to the laser imager, which requires an application software for executing the ACR/NEMA format on the laser imager or on the network-connection. However, making such application software include the medical modality or the medical network necessitates specific settings for each laser imager, whereby this is a great load for a maker.
(2) For the above-described conventional examples, it is desirable to differentiate a scaling process of image information from that of character information as to a file transferred from the medical CT or MRI. However, since the file is transferred to the laser imager with the character information being overlaid on the image information, it is difficult to differentiate the scaling process of image information from that of character information.
It is a first object of the present invention to overcome the above problem (1) and to provide a laser imager having an application software based on the protocol of X Window, which is executable from a medical modality or a medical network.
It is a second object of the present invention to overcome the above problem (2) and to provide a laser imager which can provide a better diagnostic image.
A first laser imager according to the present invention for achieving the above objects is a laser imager connected in a network with a medical modality or workstation, which has an application software for setting window information for image output, wherein said application software is accessible from said medical modality or workstation connected by the network and an interactive indication of said application software is indicated on the medical modality or workstation at an operation end.
A second laser imager is a laser imager connected in a network with a medical modality or workstation, which has an application software for setting format information for image output, wherein said application software is accessible from said medical modality or workstation connected by the network and an interactive indication of said application software is indicated on the medical modality or workstation at an operation end.
A third laser imager is a laser imager connected in a network with a medical modality or workstation, which has an application software for setting font information for image output, wherein said application software is accessible from said medical modality or workstation connected in the network and an interactive indication of said application software is indicated on the medical modality or workstation at an operation end.
A fourth laser imager is characterized in that as to a digital-connected laser imager, a scaling function for scaling image information is differentiated from that for scaling overlay information.
A fifth laser imager is characterized in that as to a digital-connected laser imager, a scaling rate for scaling image information is differentiated from that for scaling overlay information.
A sixth laser imager is characterized in that a gray-scale image is printed on a boundary of marginal space when an image is arranged on a film.
A seventh laser imager is characterized in that when a gray-scale image is printed on a boundary of marginal space in arranging an image on a film, whether the gray-scale image is to be applied to the boundary on the film or not is set.
The first laser imager having the above structure is so arranged that an interactive indication of the application software in the laser imager is executed in the medical modality or workstation so that window information is set for an output image from the medical modality.
The second laser imager is so arranged that an interactive indication of the application software in the laser imager is executed in the medical modality or workstation so that format information is set for an output image from the medical modality.
The third medical laser imager is so arranged that an interactive indication of the application software in the laser imager is executed in the medical modality or workstation so that overlay information including font information and the gray-scale may be set for an output image from the medical modality.
The fourth medical laser imager performs scaling for image information and overlay information using different scaling functions.
The fifth medical laser imager performs scaling for image information and overlay information using different scaling rates.
The sixth medical laser imager prints a gray-scale image on the boundary surrounding a medical image on a film.
The seventh medical laser imager is arranged to set as to which image is to be printed with a gray-scale image on the boundary in case the gray-scale image is printed on the boundary surrounding a medical image on a film.